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Over the past two centuries, large amounts of waste have been released into ecosystems from glass manufacturing operations. Nowadays, an increasing number of abandoned slag heaps results from the cessation of these activities and may be contaminated with metallic trace elements (MTE) formerly used in glass and crystal products. However, recent findings emphasized that derelict lands should also be recognized as a resource delivering a wide range of ecosystem services. Therefore, the major purpose of this research was to provide new insights into wasteland ecosystems of the glass industry; while assessing the relative influence of edaphic factors on biotic communities, which is still poorly understood although closely related to the potential re-use of these sites. To that end, we investigated (i) Orthoptera, diurnal Lepidoptera, plant communities, and (ii) abiotic parameters in the topsoils. Multivariate analysis revealed strong correlations between potentially phytoavailable and pseudo-total lead (Pb), cadmium (Cd) and zinc (Zn). Arsenic (As) also co-varied significantly with DTPA-extractable Pb. Despite the severe Pb contamination reported in the topsoils, wastelands of the glass industry were able to support a substantially higher than excepted biodiversity with orthopteran assemblages similar to grasslands and a diurnal Lepidoptera diversity comparable to urban parks. We also noted a positive influence of plant richness on the diurnal Lepidoptera community structure. Hence, Pb contamination does not appear to be a primary limiting factor for the establishment of these communities regarding the low mobility of Pb due to the high amount of organic matter recorded in the topsoils under subalkaline conditions. We assumed that wasteland ecosystems of the glass industry were more affected by soil fertility or land management practices. To conclude, these sites are able to provide biodiversity ecosystem services, acting as wildlife sanctuaries for Orthoptera and diurnal Lepidoptera, and strategic metals by phytoextraction in a circular economy model.

International audience

International audience

National audience; Les champignons endophytiques racinaires de type « dark septate endophytes » (DSE) pourraientaméliorer le potentiel de phytoextraction de métaux de plantes hyperaccumulatrices. Dans notre étude,nous avons isolé et identifié des souches DSE de différentes populations naturelles de Nocceaecaerulescens et montré que la forte accumulation de métaux n’était pas le facteur principal concourantà l’établissement de la diversité fongique endophytique. Certaines souches ont montré un atout positifen terme de croissance et/ou de nutrition minérale et/ou de phytoextraction de la plante hôte. Cespremières expériences ouvrent la voie à des études plus approfondies qui permettront d’améliorer leprocédé de phytoextraction.

International audience; Noccaea caerulescens, a Cd, Ni and Zn hyperaccumulator, appears to be one of the best candidates for the phytoremediation of soils contaminated by metallic trace elements. However, its use is limited by its slow growth rate and limited biomass production. Inoculation of plants with endophytic fungi could lead to a better development under both biotic and abiotic stresses, either by direct effects (secretion of phytohormones, siderophores or enzymes) or by indirect effects (resistance to pathogens), improving thus the phytoextraction potential. However, very few tests have been conducted to date with hyperaccumulating plants. In this work, five endophytic growth-promoting DSE-like fungi strains were evaluated for their potential in improving the Cd and Zn phytoextraction when grown on contaminated soils (PC18and PR). Both soils were sampled from agricultural sites contaminated by anthropogenic activities. They differed by their trace element content with respectively high and low total and available Cd and Zn concentrations in PR and PC18. DSE strains came from a collection obtained from roots of poplar grown on a metal contaminated site. After inoculation, N. caerulescenswas cultivated for three months in controlled conditions. The results highlight a significant interaction between soil and strains. Only one strain had a significant effect on the production of shoot dry biomass. We also observed variations in the effects of strains on both concentrations in major nutrients and trace elements in plant parts. Thus, the phytoextraction potential of metals could be improved following inoculation with DSE strains with, however, a strain and soil-dependent response

National audience

International audience

International audience

International audience

International audience; Noccaea caerulescensis a model plant to understand the genetic determinisms of metal hyperaccumulation as well as a potential source of cultivars for Cd phytoextraction. Sixty populations from non-metallicolous (NM), calamine (CAL) and serpentine (SER) ecotypes were phenotyped in order evaluate more extensively the genetically determined traits of the species and their variations, detect the more appropriate parental genotypes for the creation of phytoextraction cultivars, establish more representative relations between planttraits in order to give reliable information for plant breeding and for the understanding of metal homeostasis.The studied populations came from the Western distribution zone of N. caerulescens, i.e. Belgium, Finland, France, Germany, Luxembourg, Italy, Norway, Slovakia, Spain, Sweden and Switzerland. There were also two populations from Slovakia, corresponding to the Eastern part of the distribution zone of the species. Fifteen plants per population were grown until fruit maturity in a greenhouse on a homogeneous soil spiked with Cd, Ni and Zn. Development, growth and ionome variables were measured.NM and SER ecotypes appear close to each other and different from the CAL ecotype. The latter produces more inflorescences and shoot biomass, flowers sooner and reaches maturity later. Three CAL subgroups geographically structured could be distinguished according to their shoot Cd/Zn ratio, fitting to the genetic units distinguished in another. At the species level, the Ni and Zn contents were strongly correlated. Nickel accumulation was also closely associated to that of Mg and secondarily to that of Ca. The NM and SER accumulate similar amounts of Ni and Zn. Biomass production was not correlated to metal contents, suggesting no trade-off between these traits. These results confirm the genetic potential of N. caerulescensfor phytoextraction and suggest new hypothesis about the mechanisms of metal accumulation

International audience

International audience; General presentation of the Simtraces model to predict the soil to plant transfer of trace elements

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Rhizosphere microbial activity in Technosols: an opposite effect of biochar and compost. 12th International Phytotechnologies Conference

Early stage of Technosols evolution in response to organic amendments. 12th International Phytotechnologies Conference